Lined carton



y 1962 H. ALEXANDER ETAL 3,034,694

LINED CARTON Filed Feb. 10, 1960 2 Sheets-Sheet 1 e d c b I I l E D C B "A e d c b [NI/ENTOQJI 5 f/Amy ,QLExH/vDE/Z TO/IN Hum IDOL/ELL FIGS land Filed Feb. 10, 1960, Ser. No. 7,935 Claims priority, application Great Britain Feb. 13, 1959 Claims. (Cl. 229-14) This invention relates to the field of cartons, as used for example in packaging loose materials such as foodstuifs. For some purposes it is desirable to have the usual relatively rigid carton, made of cardboard or other sheeting, provided with a liner or an end-closure of inipervious air-tight, moisture-proof material to preserve the contents in good condition.

It is common to provide cartons having a separate liner or bag which is either filled and then inserted into the carton, or which may be made separately, inserted as a loose fit into the carton, and then filled whilst in the carton. However, the subsequent insertion of the filled liner or the insertion of the empty liner and its subsequent filling, are both operations which are complex and costly to carry out with the fully automatic machinery which is essential for economic large-scale packaging.

The object of the present invention is to provide a construction of package in the form of a lined carton, or carton-jacketed bag, or again a carton with end-closure, which can be manufactured with the carton material and the bag ready assembled in a collapsed condition and which can be transformed by simple deformation into an erected condition ready to receive a filling.

The term lined carton is intended to refer to a carton which eventually fully or almost fully encloses a lining, whereas carton-jacketed bag is intended to differentiate therefrom a bag of normally non-self supportcollapsed condition and an opened-tubular erected condition, and a liner constituted by a lay-flat bag of approximately the same width as the collapsed carton and having its closed end projecting sufiiciently from an end of the carton to permit developement of the bag when the carton is erected the projecting portion of the bag being a trapezium the longer parallel side of which coincides with the end of the carton and the shorter parallel side of which is a free end of the bag, the two walls of the bag being secured, at or near that end of the carton, at least to points at or adjacent to those opposed corners of the carton which move farther apart during erection. The bag may be secured about the Whole of the internal face of the carton at or adjacent to said end, and may also be secured at least partially along the length of the carton.

According to a second form of the invention, a package in the form of a carton with end-closure comprises a carton having four relatively rigid walls joined movably along their longitudinal edges and dimensioned so as to be movable into a flattened-tubular collapsed condition and an opened-tubular erected condition, and an endclosure for said carton constituted by a lay-fiat bag of approximately the same Width as the collapsed carton and projecting sufficiently from an end of the carton,

3,34,5h4 Patented May 15, 1962 to permit development of the bag when the carton is erected, the projecting portion of the bag being a trapezium the longer parallel side of which coincides with the end of the carton and the shorter parallel side of which is a free end of the bag, the bag being secured, at or adjacentto that end of the carton, about the whole of the internal or external face of the carton.

Preferably the sum of the distances between the midpoint of the free end of the bag and the point of securing of the bag to the separating corners of the carton, when the carton is in collapsed condition, is equal to the eventual separation of the said corners diagonally of the canton when in erected condition, In such a case, the bag material then pulls taut, in a pair of adjacent folds, across the extending diagonal dimension of the carton, as the latter reaches erected condition.

The projecting portion of the bag may be a symmetrical trapezium and the angle of its non-parallel sides may be selected such that upon erection of the carton the projecting portion passes into two triangular portions together covering the cross-section of the carton, plus a pair of double-walled triangular flaps each having one wall with its base joining to an edge of one of said triangular portions, said flaps lying within the confines of the carton end.

The carton may act simply as an encircling jacket for the bag, or may have means for closing its ends to form a complete carton.

The carton may, for example, be provided with a number of end flaps which can be moved down on the erlges of its side walls so as to form an end wall or part of an end wall.

Where such end flaps are provided, some or all of them may be secured to the projecting portion of the bag, thereby to be pulled inwardly, at least towards the plane of the end of the carton When the carton is moved to erected condition.

The end flaps may be so arranged that they are selfclosing, i.e. those flaps on the side walls of the carton are secured together or in pairs and oneat least of each pair of the flaps is secured to the bag material, whereby when the movement into erected condition occurs, the coupled pairs of flaps move into an inter-engaged condition forming a flat end wall for the body.

In order that the nature of the invention may be readily ascertained, the production of the constituent parts, their assembly, and the erection of a package, in accordance therewith, are hereinafter particularly described by way of example and with reference to the figures of the accompanying drawings.

In these drawings:

FIG. 1 is a plan view of a blank of carton material, shaped and scored but prior to folding.

FIG. 2 is a perspective elevation of the carton which can be formed by folding and securing in position the blank of FIG. 1.

FIG. 3 is a plan view of the blank of FIG. 1, in the form of a flattened tube prior to erection.

FIG. 4 is a plan view of a length of lay-flat heat-sealable tube from which a liner is to be formed.

FIG. 5 shows the mariner in which the tube of FIG. 4 is provided with tear-seals to close its end and provide suitable shaping.

FIG. 6 shows the liner of FIG. 5 positioned in the carton tube of FIG. 3.

FIG. 7 is an underplan of the lined carton after its erection to rectangular condition, and showing the manner in which the liner forms a base thereto.

The carton 1, as seen in FIG. 2, is constituted by any suitable semi-rigid self-supporting material such as cardboard. In erected condition it is rectangular in horizontal cross-section and has a relatively wide front wall E and rear wall C with respective end flaps e and c and relatively narrow equal side walls B and D with respect end flaps b and d.

The carton is produced by contour-cutting, e.g. from strip material, a blank as in FIG. 1, the joints 2 between the panels being scored or the like for easy bonding. When the blank is folded in half tongue A is glued or otherwise secured to wall E resulting in the flattened tube of FIG. 3. If inward opposite pressure is applied to the edges, the carton passes through various lozenge cross-sections into the rectangular condition of FIG. 2.

Referring to FIGS. 4 and 5, the liner for the carton starts as a length of relatively flexible impervious heatsealable material such as polyvinylchloride or polyethylene. Any suitable sealing device, such as a heatsealing apparatus with a contour electrode, is then used to make a three-section tear seal 4 across the bottom corners and partway along the base. The bottom corners are best formed at 45. The comparative dimensions of flattened carton and flat liner are seen in FIG. 6. With the liner in the position of FIG. 6 it is secured, e.g. by adhesive, to the inside surface of the carton. This securing takes place over the whole inner face of the walls B, C, D and E but it would suflice for the purposes of this embodiment if the liner were secured to the inner face of the carton only at lines along those edges of the carton which move apart during erection, as shown by broken lines 5 in FIG. 6.

Although the liner is shown as made up from tubular material it could be made from two separate layers of material or a single folded piece secured, e.g. by heatsealing, partially about the edges. The mouth 6 is left open for insertion of contents.

The part of the liner which projects beyond the main wall areas B, C, D, E of the carton is shaped as a symmetrical trapezium in which the free end 8 forms the shorter of the two parallel sides. The distances 1 and q, measured between the centre point 0 of this end 8 and the ends r and s of those edges 9, 10 which separate during erection of the carton, are equal in sum to the diagonal dimension 1 (FIG. 7) of the erected carton.

When inward opposite forces are applied to the edges 11 and 12 of the flat assembly of FIG. 6, as shown by the arrows, the assembly moves into a rectangular condition seen in underplain in FIG. 7. In this condition, the whole of the trapezium-shaped end portion 7 of the liner is transformed into two large equal right-angled triangular portions u and v having their hypotenuses adjacent but not join-ed, and which cover the end of the carton, plus two other double-walled equal triangular portions w and x each with one base common along the diagonal dimension of the carton and the other base of the hypotenuse of the respective triangle u or v. These double-walled portions w and x fall within the confines of the carton end, and can be made to lie flat against the triangles u and v.

The carton is provided with end flaps such as b, c, d and e at both ends. It will be appreciated that such flaps could be closed, in pairs, to form the end of the carton once the postiion of FIG. 7 has been reached, and machinery for doing this is well-known in the art. It can also be seen that the portions of liner material marked with an asterisk have each moved from a position lying in the plane of one of the four walls of the carton to a position in the plane of the end of the carton. Accordingly, if such portions are secured, e.g. by adhesive, to the adjacent end flap, such flaps will be automatically drawn down, during erection of the carton, to lie one upon the other across the end of the carton, i.e. the cartonend can be made self-closing. In another variation, only one opposed pair of end flaps is joined in this manner to the liner material, each such flap being coupled respectively to one of the other two end flaps so as to draw the latter at least partially into closing position.

The end-flaps illustrated would form a multiple-ply end wall and it will be apparent that by suitable choice of dimensions the number of plies can be varied.

It will be apparent that the same action would be obtained if the liner material formed solely an end-closure limited to the portion 7 secured in the position shown, or with an extension thereof partway up the carton. The presence of the end flap b, c, d and e is not necessary for the operation of the liner, and the carton could consist for example solely of walls B, C, D and B so as to become in effect a jacket for a bag rather than a lined carton.

We claim:

1. A lined carton comprising a carton having four relatively rigid rectangular walls joined foldably along their longitudinal edges, said walls being disposed in opposite pairs with the walls of each pair being of the same width, said four walls being movable from a flattened condition to an erected rectangular condition, a tubular liner of substantially the same width as the sum of the widths of a wall of each of said pairs of walls, opposite sides of said liner being attached at least to one end of said carton to the edges of a pair of said walls which move apart when said walls are moved from a flattened condition to a rectangular condition, and a sealed end of said liner extending beyond the end of said carton where said liner is attached a distance which allows the midpoint of said sealed end to lie a distance from the two edges of a pair of side walls which move apart which is equal to the length of the diagonal extending between the edges which move apart when said carton is in an erected rectangular condition, said sealed end having corners cut to extend inward from the end of said carton when it is in a flattened condition at an angle of 45.

2. The combination according to claim 1 wherein said tubular liner is at least the length of said carton.

3. The combination according to claim 2 with the addition of end flaps foldably joined to the ends of said walls by said sealed end of said liner.

4. The combination according to claim 3 wherein at least one of said end flaps is fixed to the material of said sealed end of said liner to be drawn inward by said sealed end as said carton is moved from a flattened to a rectangular condition.

5. The combination according to claim 4 wherein said liner is at least attached to the inside of the ends of said walls adjacent to said sealed end.

References Cited in the file of this patent UNITED STATES PATENTS 2,364,576 Waters Dec. 5, 1944 2,493,337 Buttery Jan. 3, 1950 2,801,577 Ingham Aug. 6, 1957 2,801,782 Ingham Aug. 6, 1957 

